(1) Field of the Invention
This invention relates to an immune adsorbent for use in removing autoantibodies, such as anti-DNA antibodies, anti-ENA antibodies and antinuclear antibodies and/or immune complexes from blood, plasma and other body fluids, and also to an adsorption apparatus comprising this adsorbent. The adsorbent and adsorption apparatus of the present invention are especially effective for selectively adsorbing and removing autoantibodies and/or immune complexes present in body fluids of patient's suffering from collagen diseases represented by systemic lupus erythematodes (hereinafter referred to as "SLE", for brevity), thereby purifying the body fluids, which leads to arrest of the spread of said diseases, relief to the patients suffering from said diseases and expedites curing of the diseases.
(2) Description of the Prior Art
SLE is an intractable disease which is often observed in young adults, especially young women, and which affects general organs, especially vascular tissues and connective tissues, and it is a typical example of an autoimmune disease. The cause of SLE has been unknown, but it now is considered that the presence of antinuclear antibodies and other autoantibodies in the blood of a patient suffering from SLE has serious influences on the occurrence of various disorders. Furthermore, the mechanism of depositing antigen-antibody immune complexes onto tissues is considered to have an important relation to the occurrence of vasculitis and nephritis. Recently, the plasma exchange treatment for removing malignant substances, such as antigens, antibodies and immune complexes found in the plasma of a patient, was accomplished by exchanging the patient's plasma with fresh frozen plasma or an albumin preparation, and it is confirmed that considerable effects of arresting the spread of diseases, relieving the suffering of patients and curing the diseases can be attained by this treatment.
However, this plasma exchange treatment is defective in that (1) it is difficult to readily procure a large amount of fresh frozen plasma or plasma components to replace the patient's plasma and (2) since another's plasma is utilized, the risk of infection with the hepatitis virus is very high.
As another means for removing malignant substances from the plasma of a patient, there is known an ultrafiltration method using an ultrafilter membrane. Although this method is advantageous in that the amount of plasma components supplied can be reduced, this method is defective in that (1) malignant substances having a molecular weight within a certain range are not always completely removed, (2) since the removal capacity depends solely on the molecular weight, some valuable substances are inevitably removed, and (3) if the membrane becomes clogged, such troubles as reduction of the filtration speed and change of the cut-off molecular weight occur.
Furthermore, there has been proposed a method in which autoantibodies are removed by utilizing an antigen-antibody reaction wherein an adsorbent comprising a natural polymer or similar polymers, such as DNA or a synthetic nucleic acid polymer is used, which polymer is fixed on a carrier. However, this method is poor in practical use because (i) the substance to be fixed on the carrier is expensive and (ii) if the fixed substance, which is an antigen, is set free during the treatment and introduced in the body fluid of a patient, it is liable to cause another disease.